Atherosclerosis found on carotid ultrasonography is associated with atherosclerosis on coronary intravascular ultrasonography

Evaluation of atherosclerosis as a risk factor in COPD patients by measuring the carotid intima-media thickness

BACKGROUND

This study aimed to evaluate atherosclerosis as comorbidity by measuring the carotid (bulb and common carotid artery) Carotid intima-media thickness in COPD-diagnosed patients and to evaluate the relationship of atherosclerosis with the prevalence of COPD, hypoxemia and hypercapnia.

METHODS

This study was conducted out between January 2019-December 2019 consisting of a total of 140 participants (70 COPD-diagnosed patients-70 healthy individuals). The COPD-diagnosed patients have been planned according to the selection and diagnosis criteria as per the GOLD 2019 guide. It is planned to evaluate as per prospective matching case-control study of the carotid thickness, radial gas analysis, spirometric and demographic characteristics of COPD diagnosed patients and healthy individuals.

RESULTS

The average Carotid intima-media thickness in COPD patients was 0.8746±0.161 (p<0.05), and the thickness of the carotid bulb was 1.04±0.150 (p<0.05). In the control group, the average CCA intima-media thickness was 0.6650±0.139 (p<0.05), and the thickness of the carotid bulb was 0.8250±0.15(p<0.05) For the carotid thickness that has increased in COPD diagnosed patients a significant relationship is determined between hypoxemia (p<0.05) and hypercapnia(p<0.05). A significant relationship determined between CIMT and severity of COPD (p<0.05) The CIMT was high in COPD patients with hypoxemia and hypercapnia(p<0.05).

CONCLUSION

Significant difference was determined between the severity (grades) of COPD (mild, moderate, severe, very severe) in carotid thickness. Also, CIMT was found to be high in patients who is in the early phases of the prevalence of COPD. In COPD-diagnosed patients, it was determined that severity of COPD, hypoxemia, hypercapnia and age were determining factors of atherosclerosis.

Rosuvastatin Slows Progression of Carotid Intima-Media Thickness: The METEOR-China Randomized Controlled Study

BACKGROUND

Atherosclerosis is the leading cause of cardiovascular disease worldwide, including in China. Primary prevention, through lipid-lowering, could avert development of atherosclerosis. Carotid intima-media thickness (CIMT) is a well-validated measure of atherosclerosis used in intervention studies as the primary outcome and alternative end point for cardiovascular disease events.

METHODS

This randomized, double-blind, placebo-controlled, multicenter, parallel-group study assessed the effects of rosuvastatin 20 mg/d compared with placebo on progression of CIMT over 104 weeks in Chinese people with subclinical atherosclerosis. The primary end point was the annualized rate of change in mean of the maximum CIMT measurements taken 7× over the study period from each of 12 carotid artery sites (near and far walls of the right and left common carotid artery, carotid bulb, and internal carotid artery). Secondary end points included CIMT changes at different artery sites and lipid-parameter changes. Safety was also assessed.

RESULTS

Participants were randomized (1:1) to receive rosuvastatin (n=272) or placebo (n=271). Baseline characteristics were well balanced between groups. The change in mean of the maximum CIMT of the 12 carotid sites was 0.0038 mm/y (95% CI, -0.0023-0.0100) for the rosuvastatin group versus 0.0142 mm/y (95% CI, 0.0080-0.0204) for the placebo group, with a difference of -0.0103 mm/y (95% CI, -0.0191 to -0.0016; P=0.020). For the CIMT secondary end points, the results were generally consistent with the primary end point. There were clinically relevant improvements in lipid parameters with rosuvastatin. We observed an adverse-event profile consistent with the known safety profile of rosuvastatin.

CONCLUSIONS

Rosuvastatin 20 mg/d significantly reduced the progression of CIMT over 2 years in Chinese adults with subclinical atherosclerosis and was well tolerated.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02546323.

Cardiovascular/Stroke Risk Assessment in Patients with Erectile Dysfunction-A Role of Carotid Wall Arterial Imaging and Plaque Tissue Characterization Using Artificial Intelligence Paradigm: A Narrative Review

PURPOSE

The role of erectile dysfunction (ED) has recently shown an association with the risk of stroke and coronary heart disease (CHD) via the atherosclerotic pathway. Cardiovascular disease (CVD)/stroke risk has been widely understood with the help of carotid artery disease (CTAD), a surrogate biomarker for CHD. The proposed study emphasizes artificial intelligence-based frameworks such as machine learning (ML) and deep learning (DL) that can accurately predict the severity of CVD/stroke risk using carotid wall arterial imaging in ED patients.

METHODS

Using the PRISMA model, 231 of the best studies were selected. The proposed study mainly consists of two components: (i) the pathophysiology of ED and its link with coronary artery disease (COAD) and CHD in the ED framework and (ii) the ultrasonic-image morphological changes in the carotid arterial walls by quantifying the wall parameters and the characterization of the wall tissue by adapting the ML/DL-based methods, both for the prediction of the severity of CVD risk. The proposed study analyzes the hypothesis that ML/DL can lead to an accurate and early diagnosis of the CVD/stroke risk in ED patients. Our finding suggests that the routine ED patient practice can be amended for ML/DL-based CVD/stroke risk assessment using carotid wall arterial imaging leading to fast, reliable, and accurate CVD/stroke risk stratification.

SUMMARY

We conclude that ML and DL methods are very powerful tools for the characterization of CVD/stroke in patients with varying ED conditions. We anticipate a rapid growth of these tools for early and better CVD/stroke risk management in ED patients.

Clinical Significance of Carotid Intima-Media Complex and Carotid Plaque Assessment by Ultrasound for the Prediction of Adverse Cardiovascular Events in Primary and Secondary Care Patients

Recently published recommendations from the American Society of Echocardiography on 'Carotid Arterial Plaque Assessment by Ultrasound for the Characterization of Atherosclerosis and Evaluation of Cardiovascular Risk' provoked discussion once more on the potential clinical applications of carotid intima-media complex thickness (CIMT) and carotid plaque assessment in the context of cardiovascular risk in both primary and secondary care patients. This review paper addresses key issues and milestones regarding indications, assessment, technical aspects, recommendations, and interpretations of CIMT and carotid plaque findings. We discuss lacks of evidence, limitations, and possible future directions.

Prognostic Role of Chronic Rhinosinusitis in Acute Ischemic Stroke Patients Undergoing Mechanical Thrombectomy

Background: The aim of the study was to assess the relevance of chronic rhinosinusitis (CRS) CT features to the efficacy of mechanical thrombectomy (MT) in patients with acute ischemic stroke. Methods: This study included 311 patients qualified for MT in whom the CRS features were assessed based on a CT scan, according to the Lund-Mackay (L-M) score. Clinical, inflammatory parameters, patients neurological (NIHSS) and functional status (mRS), and recanalisation efficacy (TICI) were compared between patients with mild lesions (L-M score 0–3 points)-group 1, and patients with more severe lesions (L–M score 4–24)-group 2. Results: There was a significant difference in the NIHSS on day seven after stroke onset-10 points in group 1 and 14 points in group 2, p = 0.02. NIHSS ≤ 6 points on day seven was found in 41.9% of patients in group 1, and in 27.5% in group 2, p = 0.042. There were no significant differences in mRS score and in the TICI score. L-M score, lipid abnormalities and CRP were factors associated with NIHSS ≥ 7 points on day 7. Conclusions: The CT features of CRS may be used as a prognostic tool for early prognosis assessment in stroke patients.

Diabetic patients with chronic kidney disease: Non-invasive assessment of cardiovascular risk

The prevalence and burden of diabetes mellitus and chronic kidney disease on global health and socioeconomic development is already heavy and still rising. Diabetes mellitus by itself is linked to adverse cardiovascular events, and the presence of concomitant chronic kidney disease further amplifies cardiovascular risk. The culmination of traditional (male gender, smoking, advanced age, obesity, arterial hypertension and dyslipidemia) and non-traditional risk factors (anemia, inflammation, proteinuria, volume overload, mineral metabolism abnormalities, oxidative stress, etc.) contributes to advanced atherosclerosis and increased cardiovascular risk. To decrease the morbidity and mortality of these patients due to cardiovascular causes, timely and efficient cardiovascular risk assessment is of huge importance. Cardiovascular risk assessment can be based on laboratory parameters, imaging techniques, arterial stiffness parameters, ankle-brachial index and 24 h blood pressure measurements. Newer methods include epigenetic markers, soluble adhesion molecules, cytokines and markers of oxidative stress. In this review, the authors present several non-invasive methods of cardiovascular risk assessment in patients with diabetes mellitus and chronic kidney disease.

Multimodality carotid plaque tissue characterization and classification in the artificial intelligence paradigm: a narrative review for stroke application

Cardiovascular disease (CVD) is one of the leading causes of morbidity and mortality in the United States of America and globally. Carotid arterial plaque, a cause and also a marker of such CVD, can be detected by various non-invasive imaging modalities such as magnetic resonance imaging (MRI), computer tomography (CT), and ultrasound (US). Characterization and classification of carotid plaque-type in these imaging modalities, especially into symptomatic and asymptomatic plaque, helps in the planning of carotid endarterectomy or stenting. It can be challenging to characterize plaque components due to (I) partial volume effect in magnetic resonance imaging (MRI) or (II) varying Hausdorff values in plaque regions in CT, and (III) attenuation of echoes reflected by the plaque during US causing acoustic shadowing. Artificial intelligence (AI) methods have become an indispensable part of healthcare and their applications to the non-invasive imaging technologies such as MRI, CT, and the US. In this narrative review, three main types of AI models (machine learning, deep learning, and transfer learning) are analyzed when applied to MRI, CT, and the US. A link between carotid plaque characteristics and the risk of coronary artery disease is presented. With regard to characterization, we review tools and techniques that use AI models to distinguish carotid plaque types based on signal processing and feature strengths. We conclude that AI-based solutions offer an accurate and robust path for tissue characterization and classification for carotid artery plaque imaging in all three imaging modalities. Due to cost, user-friendliness, and clinical effectiveness, AI in the US has dominated the most.

Relative Estimate of Revised Cardiovascular Risk Combining Traditional and Non-traditional Image-based CV Markers: A Kerala Based Study

BACKGROUND

Non-traditional image markers can improve the traditional cardiovascular risk estimation, is untested in Kerala based participants.

OBJECTIVE

To identify the relationship between the 'Modified CV risk' categories with traditional and non-traditional image-based risk markers. The correlation and improvement in reclassification, achieved by pooling atherosclerotic non-traditional markers with Intermediate (≥7.5% and <20%) and High (≥20%) 10-year participants is evaluated.

METHODS

The cross-sectional study with 594 participants has the ultrasound measurements recorded from the medical archives of clinical locations at Ernakulum district, Kerala. With carotid Intima-Media Thickness (cIMT) measurement, the Plaque (cP) complexity was computed using selected plaque characteristics to compute the carotid Total Plaque Risk Score (cTPRS) for superior risk tagging. Statistical analysis was done using RStudio, the classification accuracy was verified using the decision tree algorithm.

RESULTS

The mean age of the participants was (58.14±10.05) years. The mean cIMT was (0.956±0.302) mm, with 65.6% plaque incidence. With 94.90% variability around its mean, the Multinomial Logistic Regression model identifies cIMT and cTPRS, age, diabetics, Familial Hypercholesterolemia (FH), Hypertension treatment, the presence of Rheumatoid Arthritis (RA), Chronic Kidney Disease (CKD) as significant (p<0.05). cIMT and cP were found significant for 'Intermediate High', 'High' and 'Very High' 'Modified CV risk' categories. However, age, diabetes, gender and use of hypertension treatment are significant for the 'Intermediate' 'Modified CV risk' category. The overall performance of the MLR model was 80.5%. The classification accuracy verified using the decision tree algorithm has 78.7% accuracy.

CONCLUSION

The use of atherosclerotic markers shows a significant correlation suitable for a nextlevel reclassification of the traditional CV risk.

Effect of Evolocumab on Vulnerable Coronary Plaques: A Serial Coronary Computed Tomography Angiography Study

This study investigated the effects of evolocumab on vulnerable coronary plaques and factors associated with the change in stability and size of plaques in patients taking statins. Vulnerable coronary plaques were defined using coronary computed tomography (CT) angiography as having a density of <50 HU within the region of interest and a remodeling index ≥1.1. The changes in minimum CT density, remodeling index, and percent stenosis of vulnerable coronary plaques after six months of evolocumab administration were retrospectively analyzed in 136 vulnerable coronary plaques from 98 patients (68 men and 30 women; mean age: 72.9 ± 8.7 years) treated with a statin. The administration of evolocumab significantly increased the minimum CT density (39.1 ± 8.1 HU to 84.9 ± 31.4 HU, p < 0.001), reduced the remodeling index (1.29 ± 0.11 to 1.19 ± 0.10, p < 0.001), and decreased the percent stenosis (27.0 ± 10.4% to 21.2 ± 9.8%, p < 0.001). Multiple linear regression analysis revealed that baseline percent stenosis (standard coefficient (β) = -0.391, p = 0.002) independently correlated with the change in minimum CT density, whereas the baseline remodeling index (β = -0.368, p < 0.001) independently correlated with a change in the remodeling index. Evolocumab stabilized vulnerable coronary plaques and reduced their size. These results suggest that evolocumab protects against coronary artery disease progression in patients taking statins.

Carotid body enlargement in hypertension and other comorbidities evaluated by ultrasonography

BACKGROUND

Carotid body hyperactivity is important for sympathetic-related diseases and carotid body volume may partly reflect carotid bodies' activity. Our objective was to identify the association between carotid body volume and hypertension or other sympathetic-related diseases.

METHODS

Consecutive individuals, undergoing carotid ultrasonography, who were eligible for the inclusion criteria were included. The bilateral carotid bodies were detected and volumetric parameters were measured by carotid ultrasonography in clinical. Clinical data of included participants were collected and analysed.

RESULTS

A total of 1226 consecutive individuals underwent carotid ultrasonography. Carotid bodies were detected as solid, pebble-shaped, hypoechoic structures and the overall carotid body detection rate was 78.7% (965/1226). Univariate and multivariate regression analyses indicated that hypertension, chronic heart failure (CHF), chronic lung disease, smoking and high BMI were positively associated with carotid body enlargement. Compared with controls (2.63 μl), carotid body volume was significantly elevated in simple hypertensive (3.11 μl, P < 0.001), simple CHF (3.27 μl, P = 0.004) and simple smoking (3.47 μl, P < 0.001) groups. Moreover, the individuals with three comorbidities (4.05 μl) had significantly larger carotid bodies than those with one (3.23 μl, P < 0.001) or two comorbidities (3.46 μl, P = 0.017), suggesting that there existed a cumulative effect of comorbidities on carotid body volume.

CONCLUSION

Carotid body enlargement is strongly associated with hypertension and other sympathetic-related diseases or risk factors, and carotid body volume evaluated by carotid ultrasonography may be further explored as a promising screening and evaluation predictor for carotid body modulation therapy in patients with hypertension and other sympathetic-related diseases.

Circulating Factors and Ultrasono-findings are Linked to Previous Atherosclerotic Burden and Recurrent Risk

Abstract: Background:

In the progression of atherosclerosis, platelet activation and the interaction of platelets with leukocytes play a crucial role in arterial thrombus formation and are associated with the pathophysiology of carotid and cerebrovascular disease (CVD), including ischemic stroke. With aged participants, we evaluated and followed up the change in circulating factor and platelet-leukocyte aggregate levels in participants with or without CVD history. This study investigated whether circulating factor changes and ultrasonographic characteristics link to CVD risk and other relating long-term outcomes.

Materials and Methods:

Two hundred fifteen participants who enrolled in the study were divided into two groups with CVD and without CVD history. We evaluated and analyzed the correlation between ultrasonography-based morphological characteristics and circulating factor-based functional changes in both groups.

Results:

There was no difference in p-selectin level between both groups. However, activated monocyte and platelet-monocyte aggregate levels were higher in patients with previous CVD than without previous CVD. Circulating factor and ultrasonographical characteristics were correlated in the group with CVD, whereas these factors were not correlated in the group without CVD.

Conclusion:

We found that circulating blood factor levels showed a different tendency in participants with and without CVD history. The results depict that atherosclerotic severity might depend on the history of CVD and progression of atherosclerosis. We suggest that the circulating factor levels, atherosclerotic severity, and history of CVD are considered in the observation of pathologic progression to manage the development of CVD risks and CVD relating outcomes.

Nonlinear model for the carotid artery disease 10-year risk prediction by fusing conventional cardiovascular factors to carotid ultrasound image phenotypes: A Japanese diabetes cohort study

MOTIVATION

This study presents a novel nonlinear model which can predict 10-year carotid ultrasound image-based phenotypes by fusing nine traditional cardiovascular risk factors (ethnicity, gender, age, artery type, body mass index, hemoglobin A1c, hypertension, low-density lipoprotein, and smoking) with five types of carotid automated image phenotypes (three types of carotid intima-media thickness (IMT), wall variability, and total plaque area).

METHODOLOGY

Two-step process was adapted: First, five baseline carotid image-based phenotypes were automatically measured using AtheroEdge^™ (AtheroPoint^™ , CA, USA) system by two operators (novice and experienced) and an expert. Second, based on the annual progression rates of cIMT due to nine traditional cardiovascular risk factors, a novel nonlinear model was adapted for 10-year predictions of carotid phenotypes.

RESULTS

Institute review board (IRB) approved 204 Japanese patients' left/right common carotid artery (407 ultrasound scans) was collected with a mean age of 69 ± 11 years. Age and hemoglobin were reported to have a high influence on the 10-year carotid phenotypes. Mean correlation coefficient (CC) between 10-year carotid image-based phenotype and age was improved by 39.35% in males and 25.38% in females. The area under the curves for the 10-year measurements of five phenotypes IMT_ave10yr , IMT_max10yr , IMT_min10yr , IMTV_10yr , and TPA_10yr were 0.96, 0.94, 0.90, 1.0, and 1.0. Inter-operator variability between two operators showed significant CC (P < 0.0001).

CONCLUSIONS

A nonlinear model was developed and validated by fusing nine conventional CV risk factors with current carotid image-based phenotypes for predicting the 10-year carotid ultrasound image-based phenotypes which may be used risk assessment.

Carotid Intima-Media Thickness as a Cardiovascular Risk Factor and Imaging Pathway of Atherosclerosis

Assessment of carotid intima-media thickness (IMT) has emerged as a simple and noninvasive technique for measuring atherosclerotic burden. Although serum biomarkers have been linked to the risk of developing atherosclerosis, carotid IMT has the theoretical advantage of directly visualizing a final consequence of the disease itself, namely atherosclerosis in the vessel wall. The current widespread application of carotid IMT measurements has been based on the validity, standardization, and reproducibility of the measurement and the evidence that an increased carotid IMT can be regarded as an attractive biomarker of atherosclerosis and of increased cardiovascular risk, potentially useful as a therapeutic target in those at increased cardiovascular risk. The utilization of carotid IMT measurements as a surrogate end point in clinical trials evaluating a specific drug intervention may result in considerably smaller efforts and costs than when using a hard end point such as myocardial infarction, stroke, or death. In addition, the use of carotid IMT measurement as a screening tool in clinical practice in association with traditional risk factors may improve risk classification and decisions regarding therapeutic interventions. However, although carotid IMT may be correlated with clinical outcomes, changes in surrogate end points over time that result from a particular therapy may not necessarily be predictive of future cardiovascular events. Therefore, it is necessary to perform more clinical studies to clearly define the relationship between the modifications in carotid IMT and the changes in cardiovascular events. In an era of economic burden, when there is a clear combination of limited resources with high expense of innovation in drug development, carotid IMT represents a reasonable, worthwhile surrogate trial end point with a history of nearly 30 years of technical progress and clinical research. Current data strongly suggest that carotid IMT will continue to successfully be used as a valuable tool in clinical atherosclerosis research.

Wall-based measurement features provides an improved IVUS coronary artery risk assessment when fused with plaque texture-based features during machine learning paradigm

BACKGROUND

Planning of percutaneous interventional procedures involves a pre-screening and risk stratification of the coronary artery disease. Current screening tools use stand-alone plaque texture-based features and therefore lack the ability to stratify the risk.

METHOD

This IRB approved study presents a novel strategy for coronary artery disease risk stratification using an amalgamation of IVUS plaque texture-based and wall-based measurement features. Due to common genetic plaque makeup, carotid plaque burden was chosen as a gold standard for risk labels during training-phase of machine learning (ML) paradigm. Cross-validation protocol was adopted to compute the accuracy of the ML framework. A set of 59 plaque texture-based features was padded with six wall-based measurement features to show the improvement in stratification accuracy. The ML system was executed using principle component analysis-based framework for dimensionality reduction and uses support vector machine classifier for training and testing-phases.

RESULTS

The ML system produced a stratification accuracy of 91.28%, demonstrating an improvement of 5.69% when wall-based measurement features were combined with plaque texture-based features. The fused system showed an improvement in mean sensitivity, specificity, positive predictive value, and area under the curve by: 6.39%, 4.59%, 3.31% and 5.48%, respectively when compared to the stand-alone system. While meeting the stability criteria of 5%, the ML system also showed a high average feature retaining power and mean reliability of 89.32% and 98.24%, respectively.

CONCLUSIONS

The ML system showed an improvement in risk stratification accuracy when the wall-based measurement features were fused with the plaque texture-based features.

Carotid Intima-media Thickness Measurements: Relations with Atherosclerosis, Risk of Cardiovascular Disease and Application in Randomized Controlled Trials

Advances in the field of carotid ultrasound have been incremental, resulting in a steady decrease in measurement variability. Improvements in edge detection algorithms point toward increasing automation of CIMT measurements. The major advantage of CIMT is that it is completely noninvasive and can be repeated as often as required. It provides a continuous measure since all subjects have a measurable carotid wall. It is also relatively inexpensive to perform, and the technology is widely available. A graded relation between raising LDL cholesterol and increased CIMT is apparent. Increased CIMT has been shown consistently to relate the atherosclerotic abnormalities elsewhere in the arterial system. Moreover, increased CIMT predicts future vascular events in both populations from Caucasian ancestry and those from Asian ancestry. Furthermore, lipid‑lowering therapy has been shown to affect CIMT progression within 12–18 months in properly designed trials with results congruent with clinical events trials. In conclusion, when one wants to evaluate the effect of a pharmaceutical intervention that is to be expected to beneficially affect atherosclerosis progression and to reduce CV event risk, the use of CIMT measurements over time is a valid, suitable, and evidence‑based choice.

Stroke Risk Stratification and its Validation using Ultrasonic Echolucent Carotid Wall Plaque Morphology: A Machine Learning Paradigm

Stroke risk stratification based on grayscale morphology of the ultrasound carotid wall has recently been shown to have a promise in classification of high risk versus low risk plaque or symptomatic versus asymptomatic plaques. In previous studies, this stratification has been mainly based on analysis of the far wall of the carotid artery. Due to the multifocal nature of atherosclerotic disease, the plaque growth is not restricted to the far wall alone. This paper presents a new approach for stroke risk assessment by integrating assessment of both the near and far walls of the carotid artery using grayscale morphology of the plaque. Further, this paper presents a scientific validation system for stroke risk assessment. Both these innovations have never been presented before. The methodology consists of an automated segmentation system of the near wall and far wall regions in grayscale carotid B-mode ultrasound scans. Sixteen grayscale texture features are computed, and fed into the machine learning system. The training system utilizes the lumen diameter to create ground truth labels for the stratification of stroke risk. The cross-validation procedure is adapted in order to obtain the machine learning testing classification accuracy through the use of three sets of partition protocols: (5, 10, and Jack Knife). The mean classification accuracy over all the sets of partition protocols for the automated system in the far and near walls is 95.08% and 93.47%, respectively. The corresponding accuracies for the manual system are 94.06% and 92.02%, respectively. The precision of merit of the automated machine learning system when compared against manual risk assessment system are 98.05% and 97.53% for the far and near walls, respectively. The ROC of the risk assessment system for the far and near walls is close to 1.0 demonstrating high accuracy.

Lipoprotein-associated phospholipase A2: a new marker to determine cardiovascular risk in hypercholesterolemic dyslipidaemic children

Background

Inflammation and hypercholesterolaemia contribute to atherosclerotic changes which can start in childhood. Children with hyperlipidaemias are at high risk for early coronary atherosclerosis. This study evaluates the relationship between lipoprotein-associated phospholipase A2 (Lp-PLA2), carotid intima-media thickness (CIMT) and flow-mediated dilatation in hypercholesterolaemic dyslipidaemic children.

Methods

We performed a case–control study consisting of 43 cases, aged 2 to 17 years, and 24 age-matched controls. Fasting blood samples were obtained from both groups for the measurement of a lipid profile (total cholesterol, LDL-C, HDL-C and triglycerides) and Lp-PLA2 in mass units. The latter was determined with a turbidimetric immunoassay method (PlacTest, DiaDexus Inc.) applied to an automated analyser. CIMT and flow-mediated dilatation measurements were undertaken by a paediatric cardiologist, using high-resolution B-mode ultrasonography.

Results

Total cholesterol, LDL-C and Lp-PLA2 concentrations were significantly higher in the cases than in the controls ( p < 0.001 for all three parameters). While CIMT values were also significantly higher in the patients compared to the controls ( P = 0.001), flow-mediated dilatation values were significantly lower ( P = 0.001). We found positive correlations between Lp-PLA2 and total cholesterol ( r = 0.41, P = 0.001), Lp-PLA2 and LDL-C ( r = 0.36, P = 0.004), Lp-PLA2 and CIMT ( r = 0.44, P = 0.019) and LDL-C and CIMT ( r = 0.41, P = 0.032); there were negative correlations between Lp-PLA2 and flow-mediated dilatation ( r = −0.15, P = 0.045), total cholesterol and flow-mediated dilatation ( r = −0.45, P = 0.017), LDL-C and flow-mediated dilatation ( r = −0.51, P = 0.006) and CIMT and flow-mediated dilatation ( r = −0.45, P = 0.016).

Conclusion

Lp-PLA2 concentrations are significantly elevated in hypercholesterolaemic dyslipidaemic children. Given the association of Lp-PLA2 with markers of atherosclerosis (total cholesterol, LDL-C, CIMT and flow-mediated dilatation), the finding of increased concentrations of Lp-PLA2 could be used to identify early atherosclerotic changes in hypercholesterolaemic dyslipidaemic children and may inform their clinical management.

Carotid atherosclerosis is associated with left ventricular diastolic function

BACKGROUND

It has been reported that carotid intima-media thickness (IMT) correlates with the risk of stroke or cardiovascular disease. The purpose of this study was to analyze the relationships between echocardiographic findings and carotid atherosclerosis.

METHODS

A total of 234 patients (62 ± 15 years) were referred for echocardiography to evaluate the left ventricular (LV) function. The LV ejection fraction, the ratio of the peak velocity of early rapid filling and the peak velocity of atrial filling (E/A), and the peak early diastolic mitral annular velocity (e') were obtained by echocardiography. The maximum IMT (Max-IMT) and plaque score (PS) were measured by carotid ultrasonography within 1 month of the echocardiographic examination.

RESULTS

The mean values of Max-IMT and carotid PS were 2.41 ± 1.23 mm and 8.5 ± 6.3, respectively. The decreased mean E/A (0.94 ± 0.39) and mitral e' (5.5 ± 1.9 cm/s) indicated LV diastolic dysfunction. A good correlation was observed between Max-IMT and PS (r = 0.83, p < 0.0001). It was shown that 2.8 mm of Max-IMT was equivalent to 10.1 of carotid PS, which indicated severe carotid atherosclerosis. In multiple logistic stepwise regression analysis, among the echocardiographic parameters, only e' was independently associated with severe carotid atherosclerosis (Max-IMT ≥ 2.8 mm or PS ≥ 10.1).

CONCLUSIONS

The present study demonstrated that decreased early diastolic mitral annular velocity relates to the parameter reflecting carotid atherosclerosis. Therefore, the presence of severe carotid atherosclerosis may affect LV diastolic dysfunction.

PCA-based polling strategy in machine learning framework for coronary artery disease risk assessment in intravascular ultrasound: A link between carotid and coronary grayscale plaque morphology

BACKGROUND AND OBJECTIVE

Percutaneous coronary interventional procedures need advance planning prior to stenting or an endarterectomy. Cardiologists use intravascular ultrasound (IVUS) for screening, risk assessment and stratification of coronary artery disease (CAD). We hypothesize that plaque components are vulnerable to rupture due to plaque progression. Currently, there are no standard grayscale IVUS tools for risk assessment of plaque rupture. This paper presents a novel strategy for risk stratification based on plaque morphology embedded with principal component analysis (PCA) for plaque feature dimensionality reduction and dominant feature selection technique. The risk assessment utilizes 56 grayscale coronary features in a machine learning framework while linking information from carotid and coronary plaque burdens due to their common genetic makeup.

METHOD

This system consists of a machine learning paradigm which uses a support vector machine (SVM) combined with PCA for optimal and dominant coronary artery morphological feature extraction. Carotid artery proven intima-media thickness (cIMT) biomarker is adapted as a gold standard during the training phase of the machine learning system. For the performance evaluation, K-fold cross validation protocol is adapted with 20 trials per fold. For choosing the dominant features out of the 56 grayscale features, a polling strategy of PCA is adapted where the original value of the features is unaltered. Different protocols are designed for establishing the stability and reliability criteria of the coronary risk assessment system (cRAS).

RESULTS

Using the PCA-based machine learning paradigm and cross-validation protocol, a classification accuracy of 98.43% (AUC 0.98) with K=10 folds using an SVM radial basis function (RBF) kernel was achieved. A reliability index of 97.32% and machine learning stability criteria of 5% were met for the cRAS.

CONCLUSIONS

This is the first Computer aided design (CADx) system of its kind that is able to demonstrate the ability of coronary risk assessment and stratification while demonstrating a successful design of the machine learning system based on our assumptions.

A new method for IVUS-based coronary artery disease risk stratification: A link between coronary & carotid ultrasound plaque burdens

Interventional cardiologists have a deep interest in risk stratification prior to stenting and percutaneous coronary intervention (PCI) procedures. Intravascular ultrasound (IVUS) is most commonly adapted for screening, but current tools lack the ability for risk stratification based on grayscale plaque morphology. Our hypothesis is based on the genetic makeup of the atherosclerosis disease, that there is evidence of a link between coronary atherosclerosis disease and carotid plaque built up. This novel idea is explored in this study for coronary risk assessment and its classification of patients between high risk and low risk. This paper presents a strategy for coronary risk assessment by combining the IVUS grayscale plaque morphology and carotid B-mode ultrasound carotid intima-media thickness (cIMT) - a marker of subclinical atherosclerosis. Support vector machine (SVM) learning paradigm is adapted for risk stratification, where both the learning and testing phases use tissue characteristics derived from six feature combinational spaces, which are then used by the SVM classifier with five different kernels sets. These six feature combinational spaces are designed using 56 novel feature sets. K-fold cross validation protocol with 10 trials per fold is used for optimization of best SVM-kernel and best feature combination set. IRB approved coronary IVUS and carotid B-mode ultrasound were jointly collected on 15 patients (2 days apart) via: (a) 40MHz catheter utilizing iMap (Boston Scientific, Marlborough, MA, USA) with 2865 frames per patient (42,975 frames) and (b) linear probe B-mode carotid ultrasound (Toshiba scanner, Japan). Using the above protocol, the system shows the classification accuracy of 94.95% and AUC of 0.95 using optimized feature combination. This is the first system of its kind for risk stratification as a screening tool to prevent excessive cost burden and better patients' cardiovascular disease management, while validating our two hypotheses.

CT-based abdominal aortic calcification score as a surrogate marker for predicting the presence of asymptomatic coronary artery disease

OBJECTIVES

To assess the value of a CT-based abdominal aortic calcification (AAC) score as a surrogate marker for the presence of asymptomatic coronary artery disease (CAD).

METHODS

The AAC scores of 373 patients without cardiac symptoms who underwent both screening coronary CT angiography and abdominal CT within one year were calculated according to the Agatston method. Logistic regression was used to derive two multivariate models from traditional cardiovascular risk factors, with and without AAC scores, to predict the presence of CAD. The AAC score and the two multivariate models were compared by calculating the area under the receiver operating characteristic curve (AUC) and the net reclassification improvement (NRI).

RESULTS

The AAC score alone showed a marginally higher AUC (0.823 vs. 0.767, P = 0.061) and significantly better risk classification (NRI = 0.158, P = 0.048) than the multivariate model without AAC. The multivariate model using traditional factors and AAC did not show a significantly higher AUC (0.832 vs. 0.823, P = 0.616) or NRI (0.073, P = 0.13) than the AAC score alone. The optimal cutoff value of the AAC score for predicting CAD was 1025.8 (sensitivity, 79.5 %; specificity, 75.9 %).

CONCLUSIONS

AAC scores may serve as a surrogate marker for the presence or absence of asymptomatic CAD.

KEY POINTS

• Severe vascular calcification indicates a high probability of coronary artery disease. • Vascular calcification in the abdominal aorta can be quantified by computed tomography. • Abdominal CT could lead to early detection of asymptomatic coronary artery disease.

The SYNTAX score does not predict presence of carotid disease in a multivessel coronary disease population

BACKGROUND

Numerous reports have shown the relationship between carotid artery atherosclerosis and coronary artery disease (CAD). However, the association between complex CAD evaluated by SYNTAX score (SxScore) and prevalence of carotid lesion (CL) has not been fully investigated. We sought to assess the prevalence of carotid atherosclerosis in patients with multivessel CAD assessed by SxScore and the relationship between SxScore severity and features of carotid atherosclerosis.

METHODS AND RESULTS

Subjects were 204 consecutive patients with multivessel CAD assessed by coronary angiography and no previous history of carotid atherosclerosis that underwent carotid ultrasound scan from June 2012 to 2013. Presence of CL, significant carotid disease (SCD) and carotid plaque morphology was evaluated. At least one CL was found in 159 patients (77.9%) with no significant difference among SxScore groups (P = 0.20 and P = 0.54, respectively). High prevalence of complex carotid plaque (CCP) was found without significant different distribution in SxScore groups (P = 0.69). Age was independently associated with the presence of CL [odds ratio (OR) 1.055; 95% confidence interval (CI): 1.015-1.097; P = 0.007] and SCD (OR 1.057; 95% CI: 1.008-1.097; P = 0.019). Age and diabetes were independently associated with CCP (OR 1.58; 95% CI: 1.023-1.095; P = 0.001; OR 1.848; 95% CI: 1.026-3.327; P = 0.041). SxScore was not independently associated with CL, SCD and CCP (all P > 0.2).

CONCLUSIONS

We found high prevalence of CL in patients with multivessel complex CAD. However, SxScore does not seem to correlate with carotid atherosclerosis.

Metabolic syndrome and carotid intima-media thickness in chronic obstructive pulmonary disease

Background

The aim of this study is to investigate the prevalence of metabolic syndrome (MetS), carotid intima media thickness (IMT), and serum C-reactive protein (CRP) levels in patients with chronic obstructive pulmonary disease (COPD), and the possible relationships among them.

Methods

Fifty stable COPD patients and 40 healthy controls were included in the study. The participants were further divided into four groups according to their smoking status. Pulmonary function tests were performed in COPD patients. Anthropometric measurements and blood chemistry analysis, serum CRP levels and carotid intima-media thickness (IMT) measurements were performed in all the study population.

Results

Prevalence of metabolic syndrome was 43% in COPD patients and 30% in the control group (p = 0.173). FEV₁% and FEV₁/FVC were higher in COPD patients with MetS (p = 0.001 and p = 0.014, respectively) compared to those without MetS. Prevalence of MetS was significantly different among the COPD patients with different stages (p = 0.017) with the highest value in stage 2 (59%). Carotid IMT was significantly higher in COPD patients than in control group (1.07 ± 0.25 mm and 0.86 ± 0.18 mm, respectively; p < 0.001). Serum CRP levels were not different in COPD patients and controls, however they were higher in individuals with MetS compared to those without MetS regardless of COPD presence (p = 0.02).

Conclusions

Early markers of atherogenesis, in terms of carotid IMT, were found to be higher in COPD patients than in healthy controls. MetS prevalence was observed to decrease as the severity of airflow obstruction increased. Therefore, screening COPD patients for these cardiovascular risk factors would be a novel approach even in absence of symptoms.

Long-term changes in carotid intima-media thickness among HIV-infected children and young adults

BACKGROUND

HIV-infected patients are at increased risk of cardiovascular disease (CVD). This study assessed long-term changes in carotid intima-media thickness (IMT) as a surrogate marker for CVD risk in HIV-infected children and young adults.

METHODS

This was a longitudinal, observational study comparing carotid IMT in HIV-infected subjects who were 2-21 years old to matched controls over 144 weeks.

RESULTS

A total of 34 HIV-infected subjects and 29 controls were included in the analyses. Among the HIV-infected group, median age was 10 years, 74% were black, and 65% were female. Overall, 91% were perinatally-infected with 82% on antiretroviral therapy and a median CD4(+) T-cell count of 681 cells/mm(3). At baseline, HIV-infected subjects had increased internal carotid artery (ICA) and common carotid artery (CCA) IMT (ICA, HIV-infected 0.90 mm versus controls 0.73 mm; P<0.01; CCA, HIV-infected 1.00 mm versus controls 0.90 mm; P=0.02). Relatively large changes in ICA and CCA IMT were seen from year to year in both groups. However, by week 144, there were no net changes in ICA or CCA IMT within the HIV-infected group. In the controls, CCA increased 0.1 mm and ICA increased 0.17 mm from baseline to week 144. ICA and CCA IMT were similar between groups by 144 weeks.

CONCLUSIONS

Despite variations from year to year in carotid IMT in HIV-infected children and healthy controls, likely due to arterial growth and/or luminal diameter change, little or no net change occurred in carotid IMT over the entire 144-week study period. This suggests that only small net changes occur over time in HIV-infected children despite an increased long-term risk of CVD.

Quantitative analysis of ultrasound contrast flow behavior in carotid plaque neovasculature

Intraplaque neovascularization is considered as an important indication for plaque vulnerability. We propose a semiautomatic algorithm for quantification of neovasculature, thus, enabling assessment of plaque vulnerability. The algorithm detects and tracks contrast spots using multidimensional dynamic programming. Classification of contrast tracks into blood vessels and artifacts was performed. The results were compared with manual tracking, visual classification and maximal intensity projection. In 28 plaques, 97% of the contrast spots were detected. In 89% of the objects, the automatic tracking determined the contrast motion with an average distance of less than 0.5 mm from the manual marking. Furthermore, 75% were correctly classified into artifacts and vessels. The automated neovascularization grading agreed within 1 grade with visual analysis in 91% of the cases, which was comparable to the interobserver variability of visual grading. These results show that the method can successfully quantify features that are linked to vulnerability of the carotid plaque.

Impact of combined assessment of coronary artery calcium score, carotid artery plaque score, and brachial-ankle pulse wave velocity for early coronary revascularization in patients with suspected coronary artery disease

Coronary artery calcium score (CACS) measured by multi-detector computed tomography, carotid plaque score (CPS) measured by carotid artery ultrasound, and brachial-ankle pulse wave velocity (baPWV) are noninvasive screening tools for coronary artery disease. The aim of this study was to determine whether the combination of CACS, CPS, and baPWV improves the prognostic value for future cardiac events. CACS, CPS, and baPWV were assessed in 77 patients (mean age, 65 years, 49 males) undergoing invasive coronary angiography. ECG-triggered MSCT was used to assess CACS. CPS was defined as the sum of all plaque heights in bilateral carotid arteries. The highest baPWV was used for analysis. Cardiac events were defined as cardiac death, nonfatal myocardial infarction, or coronary revascularization. Thirty-two cardiac events (41.6%) occurred during follow-up (23.6 ± 20.8 months), consisting of 28 PCIs and 4 CABGs. The best cutoff values of positive CACS, CPS, and baPWV for predicting cardiac events were ≥ 50, ≥ 5, and ≥1.6 m/second, respectively. For the combination of the 3 modalities, the positive test was defined as having at least 1 positive result by each method. The negative predictive value of all 3 modalities combined was better than that of CACS alone. The event-free rate was higher in patients with negative results for all 3 parameters compared with those that were positive (100% versus 44.8%, P < 0.0001). The prognostic value of using combined assessment of CACS, CPS, and baPWV is more effective for predicting cardiac events than CACS alone.

Constrained snake vs. conventional snake for carotid ultrasound automated IMT measurements on multi-center data sets

Accurate intima-media thickness (IMT) measurement of the carotid artery from minimal plaque ultrasound images is a relevant clinical need, since IMT increase is related to the progression of atherosclerosis. In this paper, we describe a novel dual snake-based model for the high-performance carotid IMT measurement, called Carotid Measurement Using Dual Snakes (CMUDS). Snakes (which are deformable contours) adapt to the lumen-intima (LI) and media-adventitia (MA) interfaces, thus enabling the IMT computation as distance between the LI and MA snakes. However, traditional snakes might be unable to maintain a correct distance and in some spatial location along the artery, it might even collapse between them or diverge. The technical improvement of this work is the definition of a dual snake-based constrained system, which prevents the LI and MA snakes from collapsing or bleeding, thus optimizing the IMT estimation. The CMUDS system consists of two parametric models automatically initialized using the far adventitia border which we automatically traced by using a previously developed multi-resolution approach. The dual snakes evolve simultaneously and are constrained by the distances between them, ensuring the regularization of LI/MA topology. We benchmarked our automated CMUDS with the previous conventional semi-automated snake system called Carotid Measurement Using Single Snake (CMUSS). Two independent readers manually traced the LIMA boundaries of a multi-institutional, multi-ethnic, and multi-scanner database of 665 CCA longitudinal 2D images. We evaluated our system performance by comparing it with the gold standard as traced by clinical readers. CMUDS and CMUSS correctly processed 100% of the 665 images. Comparing the performance with respect to the two readers, our automatically measured IMT was on average very close to that of the two readers (IMT measurement biases for CMUSS was equal to -0.011±0.329mm and -0.045±0.317mm, respectively, while for CMUDS, it was 0.030±0.284mm and -0.004±0.273mm, respectively). The Figure-of-Merit of the system was 98.5% and 94.4% for CMUSS, while 96.0% and 99.6% for CMUDS, respectively. Results showed that the dual-snake system CMUDS reduced the IMT measurement error accuracy (Wilcoxon, p<0.02) and the IMT error variability (Fisher, p<3×10(-2)). We propose the CMUDS technique for use in large multi-centric studies, where the need for a standard, accurate, and automated IMT measurement technique is required.

Comparative effectiveness of the approaches to correct vascular structural and functional disturbances in postmenopausal women

Aim.To compare the effects of Mildronate and hormone replacement therapy (HRT) with estradiol (1 mg) and drospirenone, DSPR (2 mg) on circadian blood pressure (BP) profile, arterial structure and function, and vascular stiffness parameters in women with early postmenopause and climacteric syndrome (CS).Material and methods.The study included 94 women with early postmenopause and CS, who provided written informed consent to participate and were divided into two groups. Group I included 36 women receiving Mildronate (500 mg twice a day), while Group II included 28 women who were administered, according to clinical indications, HRT (1 mg 17β-estradiol and 2 mg DRSP once a day). The control group (CG) included 30 women who did not receive either Mildronate or DRSP. At baseline and 16 weeks later, all participants underwent the assessment of blood biochemistry; intima-media thickness (IMT) of common carotid artery (CCA); endothelium-dependent vasodilatation (EDVD) of brachial artery (BA); antithrombogenic activity of vascular wall; aortal pulse wave velocity (aPWV); arterial stiffness; and 24-hour BP monitoring (BPM).Results.The study demonstrated positive effects of Mildronate therapy and HRT (1 mg 17β-estradiol and 2 mg DRSP) on metabolic status, circadian dynamics and variability (Var) of BP, and arterial structure and function. The largest positive changes in blood lipid profile were observed in Group I and II patients. By the end of the study, these patients demonstrated significantly decreased levels of systolic and diastolic BP and reduced BP Var, particularly in Group II. Mildronate therapy, but not HRT, was associated with normalisation of vascular wall antiaggregant potential. Group II demonstrated a significant reduction in CCA IMT levels, with a similar tendency in Group I. In both groups, the degree of endothelial dysfunction (ED) decreased, which was manifested in increased BA EDVD, decreased aPWV, and reduced arterial stiffness and was more pronounced in Group II.Conclusion.In menopausal women with CS, the effects of Mildronate and HRT on metabolic, structural, and functional disturbances were similar. Therefore, Mildronate therapy could be a new method of correction of these systemic disturbances.

Fully automated dual-snake formulation for carotid intima-media thickness measurement. A new approach

Automated computer-aided detection systems for measurement of the carotid intima-media thickness (IMT) are becoming popular. These systems yield lumen-intima (LI) and media-adventitia (MA) borders. In this work, we developed and validated a novel and patented completely automated IMT measurement system called carotid measurement using dual snakes (CMUDS): a class of AtheroEdge system (Global Biomedical Technologies, Inc, Roseville, CA). CMUDS is modeled as a dual parametric system corresponding to LI and MA borders with initialization from the far adventitia layer. The novelty of CMUDS is the first-order absolute moment-based external energy, which provides stable deformation. The dual snakes evolve simultaneously and are forced to maintain a regularized distance to prevent collapsing or bleeding. Two independent readers manually traced the LI/MA boundaries of a multi-institutional, multi-ethnic, and multi-scanner database of 665 longitudinal images for performance evaluation. CMUDS was also benchmarked against a previously developed automated technique. CMUDS correctly processed 660 images (99.2% success). The differences between the CMUDS and two manual IMT measurements (mean ± SD) were 0.013 ± 0.216 and -0.021 ± 0.197 mm, respectively. The corresponding figures of merit for CMUDS compared to reader tracings were 98.4% and 97.5%. Compared to the previous technique (IMT differences, 0.022 ± 0.276 and -0.012 ± 0.266 mm), CMUDS improved accuracy (Wilcoxon P < 0.009) and variability (Fisher P < 10(-8)). Among different resolution images from original equipment manufacturer ultrasound scanners, CMUDS performed best with high-resolution images corresponding to 0.0789 mm/pixel. Accuracy in IMT measurement with the proposed automated CMUDS technique makes this system adaptable to large multi-center studies, in which such an IMT measurement system would be very useful tool.

Cardiorenal disturbances in perimenopausal women

Aim. To identify early signs of renal dysfunction; to investigate the associations between renal function and vascular remodelling; to evaluate the role of metabolic and hydrodynamic disturbances in the development of cardiorenal syndrome among perimenopausal women; and to assess the potential of hormone replacement therapy (17β-estradiol 1 mg and drospirenone 2 mg) for the correction of the above-mentioned disturbances. Material and methods. In total, 69 perimenopausal women were divided into two groups. Group I included 69 premenopausal women, while Group II consisted of 43 women in early postmenopause. Mean age in Group I was 49,0 years (95% CI 48,0-51,0 years); in Group II, it was 54,0 (50,0-56,0) years (p<0,01). Age at menopause reached 50,3 (48,0-52,0) years, with median duration of menopause of 3,5 (2,0-5,0) years. All participants underwent biochemical blood tests (creatinine (Cr), uric acid (UA), lipid profile, and glucose tolerance test (GTT)). Large elastic artery remodelling was assessed by intima-media thickness (IMT) of common carotid artery (CCA). Non-invasive assessment of endothelial vasoregulatory function involved the measurement of brachial artery (BA) endothelium-dependent vasodilatation (EDVD) in the reactive hyperemia test (RHT). Renal function was assessed by glomerular filtration rate (GFR) and Cr clearance (CrC). Monoalbuminuria (MAU) was qualitatively assessed with a urine strip test. Postmenopausal women were additionally divided into two groups: 23 patients were administered HRT (17β-estradiol 1 mg and drospirenone 2 mg; Angelique medication), while 20 women not receiving HRT comprised a control group. At the end of the study, after 12 months, the assessment of metabolic status, body mass dynamics, endothelial vasoregulatory function, and CCA IMT was repeated. Results. In most postmenopausal women, lipid and carbohydrate metabolism disturbances were observed, which were typical for metabolic syndrome (MS). Lipid metabolism disturbances were observed as early as in premenopause, but reached their maximum during early postmenopause. Postmenopausal women, compared to their peers in premenopause, had significantly higher fasting and postprandial levels of blood glucose. Structural and functional changes in vascular wall were more severe in postmenopausal vs. premenopausal women (p<0,001). While blood flow velocity in the RHT was comparable in both groups, postmenopausal women did not demonstrate a comparable increase in BA EDVD, in contrast to premenopausal females. This could point to the decrease in BA sensitivity to endothelial shear stress among women in postmenopause. Reduced GFR was observed only in postmenopausal women. MAU was registered in premenopausal women with normal GFR, as well as in postmenopausal females. These data on independent role of MAU and reduced GFR suggest an increase in the proportion of women with subclinical renal injury, as a manifestation of target organ damage. Conclusion. The associations between vascular structure and function, renal function, and main MS components were demonstrated. HRT (17β-estradiol 1 mg and drospirenone 2 mg) had beneficial effects on BP dynamics, visceral obesity, metabolic status, and arterial structure and function.

Carotid intima–media thickness: a suitable alternative for cardiovascular risk as outcome?

BACKGROUND

Surrogate markers for cardiovascular disease might be of great value in observational research, clinical trials, and clinical practice. Carotid intima-media thickness (CIMT) is probably the most commonly used marker for atherosclerotic disease as an alternative for cardiovascular morbidity and mortality. A suitable marker for atherosclerosis, however, should meet several criteria before it can be validly used.

METHODS AND RESULTS

We reviewed the literature following a set of criteria for a surrogate marker. These include a comparison with a 'gold standard'; adequate reproducibility; cross-sectional relations with established risk factors and prevalent disease; relations with severity of atherosclerosis elsewhere in the arterial system; relations with the occurrence with future events; ability for a biomarker to change over time; ability to be affected by interventions over time; and relations between change over time in biomarker level and change in risk. A large number of studies from a variety of populations provide evidence for the validity of CIMT as a suitable measure of atherosclerotic disease. Data on the relation between change in CIMT and change in risk, however, is much sparser.

CONCLUSION

CIMT progression meets the criteria of a surrogate for cardiovascular disease endpoints and may be considered as a valid alternative for cardiovascular events as outcome. Further studies should examine the association between changes in CIMT and changes in risk for future events.

Carotid plaque vulnerability: quantification of neovascularization on contrast-enhanced ultrasound with histopathologic correlation

OBJECTIVE

The purpose of this research is to develop a computerized method to quantify carotid plaque neovascularization on contrast-enhanced ultrasound images and to compare the results with the histopathologic analysis of the plaque.

SUBJECTS AND METHODS

Twenty-seven patients (age range, 48-84 years; mean [± SD] age, 68.4 ± 9.72 years) were recruited before endarterectomy. Contrast-enhanced ultrasound examination of the carotid artery was performed by applying low mechanical index and harmonics with pulse inversion. An algorithm was developed that implemented several image processing methods to automatically quantify neovascularization and reconstruct the vascular tree in the atheromatous plaque. Neovascularization and the number of inflammatory cells seen on histopathologic analysis of the plaque after endarterectomy were compared with neovascularization determined by the computerized method. The mean (± SD) ratios of the ultrasound and histopathologic measurements were calculated.

RESULTS

In five patients, heavy calcification of the plaque prevented visualization of plaque texture. Intraplaque neovascularization on contrast-enhanced ultrasound images was significant in 19 patients and low in three patients. The ratio of the neovascularization area to the total plaque area on contrast-enhanced ultrasound images was well correlated with the same histopathologic ratio (R(2) = 0.7905) and with the number of inflammatory cells present in the plaque (R(2) = 0.6109). The histopathologic ratio and the number of intraplaque inflammatory cells also were well correlated (R(2) = 0.7034).

CONCLUSION

The newly developed method allowed quantification of the intraplaque neovascularization as a feature of vulnerability in the carotid plaque and proved to be highly correlated with histopathologic results.

Carotid intima media thickness, inflammatory markers, and endothelial activation markers in HIV Patients with lipoatrophy increased at 48 weeks regardless of use of rosiglitazone or placebo

Rosiglitazone may be useful for the treatment of antiretroviral therapy-associated lipoatrophy, but an association with cardiovascular disease (CVD) has been questioned in diabetics. We evaluated rosiglitazone's effect on surrogate markers of CVD in HIV-infected individuals with lipoatrophy. HIV(+) patients with lipoatrophy on thymidine-sparing regimens were randomized to rosiglitazone vs. placebo for 48 weeks. We serially assessed carotid IMT, fasting metabolic profiles, tumor necrosis factor (TNF)-α, soluble receptors (sTNFRI and II), interleukin (IL)-6, high-sensitivity C-reactive protein (hsCRP), myeloperoxidase (MPO), and endothelial activation markers [von Willebrand factor (vWF), soluble intercellular cell adhesion molecules-1 (sICAM-1), and vascular cell adhesion molecules-1 (sVCAM-1)]. Seventy-one subjects enrolled: 17% were female and 51%were white. Baseline characteristics were similar between groups except for higher total cholesterol in the placebo group (p = 0.04). At 48 weeks, common carotid artery (CCA) IMT changed significantly (p ≤ 0.05) within but not between the groups (p = 0.36): the median (IQR) increase was 0.10 (0.05, 0.25) mm and 0.15 (0, 0.25) mm in the rosiglitazone and placebo groups, respectively. hsCRP, sTNFRI and II, sVCAM-1, and vWF changed significantly (p ≤ 0.02) within but not between groups. Total cholesterol increased significantly in the rosiglitazone group (p = 0.008). In our study of virologically controlled subjects with lipoatrophy, rosiglitazone did not independently increase carotid IMT, endothelial activation, and inflammatory cytokines.

Longitudinal changes in carotid intima-media thickness and cardiovascular risk factors in human immunodeficiency virus-infected children and young adults compared with healthy controls

OBJECTIVES

HIV-infected patients are at increased risk of cardiovascular disease (CVD). This study assessed longitudinal changes in carotid intima-media thickness (cIMT) as a surrogate marker for CVD, and determined the relationship between cIMT and cardiovascular risk factors in HIV infected children/young adults.

METHODS

This was a longitudinal, observational study comparing cIMT,fasting metabolic profile, and C-reactive protein in HIV-infected subjects 2 to 21 years old to matched controls at baseline and 48 weeks.

RESULTS

Thirty-five HIV + subjects and 37 controls were included in the analysis. Among HIV + subjects, the median age was 10 years, body mass index was 18.7 kg/m2, 37% were male, CD4 count was 32%, 77% had HIV-RNA 400 copies/mL, and 86% were on antiretrovirals. At baseline,HIV + had higher lipids and C-reactive protein. HIV-infected had higher internal carotid artery (ICA) and common carotid artery (CCA) IMT (mm)(ICA: HIV + , 0.90; controls, 0.78 [P = 0.01]; CCA: HIV + , 1.00; controls,0.95 [P = 0.05]). At 48 weeks, CD4% increased and low-density lipoprotein decreased in HIV-infected subjects. ICA and CCA median changes for HIV-infected subjects were -0.23 and -0.15 mm, respectively (both P 0.01). In controls, only CCA changed (P = 0.04). Between-group changes were not significant, except when only 31 perinatally infected HIV - subjects and the controls were compared (CCA P = 0.04). In multiple regression analyses of HIV + subjects, antiretroviral therapy duration and CD4% were associated with cIMT changes.

CONCLUSIONS

Higher cIMT was found in HIV-infected subjects than in healthy controls, but at 48 weeks, cIMT was similar between groups. These data suggest that HIV-infected children/young adults are at high risk of CVD, but lipid control, immune restoration, and viral suppression with continuous antiretroviral therapy may prevent its worsening.

Ultrasound-assessed perirenal fat is related to increased ophthalmic artery resistance index in HIV-1 patients

Background

The introduction of highly active antiretroviral therapy (HAART) has dramatically changed the prognosis of human immunodeficiency virus (HIV) infection, with a significant decline in morbidity and mortality.

Changes in body fat distribution are a common finding in individuals with HIV infection being treated with antiretrovirals, and this condition (collectively termed lipodystrophy syndrome) is associated with depletion of subcutaneous fat, increased triglycerides and insulin resistance. Obesity, particularly visceral obesity, is associated with increased risk of cardiovascular disease. Therefore, estimating visceral fat distribution is important in identifying subjects at high risk for cardiovascular disease.

The aim of our study was to evaluate whether perirenal fat thickness (PRFT), a parameter of central obesity, is related to ophthalmic artery resistance index (OARI), an index of occlusive carotid artery disease in HIV-1 infected patients.

Methods

We enrolled 88 consecutive HIV-1-infected patients receiving highly active antiretroviral therapy for more than 12 months, in a prospective cohort study. Echographically measured PRFT and OARI, as well as serum metabolic parameters, were evaluated. PRFT and OARI were measured by 3.75 MHz convex and 7.5 MHz linear probe, respectively.

Results

The means of PRFT and OARI in HIV-1-infected patients with visceral obesity was considerably higher than in patients without it (p < 0.0001 and p < 0.001, respectively). Using the average OARI as the dependent variable, total serum cholesterol level, HDL, triglycerides, glycemia, sex, blood pressure, age and PRFT were independent factors associated with OARI. A PRFT of 6.1 mm was the most discriminatory value for predicting an OARI > 0.74 (sensitivity 78.9%, specificity 82.8%).

Conclusions

Our data indicate that ultrasound assessment of PRFT may have potential as a marker of increased endothelial damage with specific involvement of the ocular vascular region in HIV-1-infected patients.

Sonographically measured perirenal fat thickness: an early predictor of atherosclerosis in HIV-1-infected patients receiving highly active antiretroviral therapy?

PURPOSE

The aim of our study was to evaluate whether perirenal fat thickness (PRFT), a parameter of central obesity, is related to carotid intima-media thickness (IMT), an index of atherosclerosis in human immunodeficiency virus (HIV)-1-infected patients.

METHODS

We enrolled 70 consecutive HIV-1-infected patients receiving highly active antiretroviral therapy for more than 12 months, in a prospective cohort study. Sonographically measured PRFT and carotid IMT, as well as serum metabolic parameters, were evaluated. PRFT and IMT were measured using 3.75-MHz convex and 7.5-MHz linear probes, respectively.

RESULTS

The mean PRFT and IMT in HIV-1-infected patients with visceral obesity was significantly greater than those in patients without it (p < 0.0001 and p < 0.01, respectively). Using the average IMT as the dependent variable in regression analysis, PRFT was an independent factor associated with carotid IMT (p < 0.05). A PRFT of 6.4 mm was the most discriminatory value for predicting an IMT >or= 0.9 mm (sensitivity 83.3%, specificity 83.9%). Subjects with visceral obesity had a progressively increasing carotid IMT on the 12-month measurement (p < 0.05).

CONCLUSION

Our data demonstrated that PRFT measurement could be used as an early predictor of IMT increase in HIV-1-infected patients receiving highly active antiretroviral therapy.

Leukocyte telomere length is associated with measures of subclinical atherosclerosis

AIMS

Our aim was to test the association of mean leukocyte telomere length (LTL) with ultrasonic measures of subclinical atherosclerosis such as intima-media thickness in the common carotid (IMTcc) and sum of plaque areas (SPA) and with serological markers.

METHODS AND RESULTS

Carotid and femoral bifurcations were scanned in 762 general population volunteers (46% men) over 40. Four features were considered: (a) IMTcc, (b) sum plaque areas of carotid plaques (SPAcar), (c) sum plaque area of common femoral plaques (SPAfem) and (d) sum plaque area (SPA--sum of the plaque areas of the largest plaques present in each of both carotid and femoral bifurcations). Mean LTL was determined with a quantitative real-time PCR-based method. IMTcc was strongly associated with mean LTL both before and after correction for traditional risk factors (B=-0.002; 95% CI=-0.004 to -0.00; p=0.014). In sex-specific analysis, the association was stronger in men (p for sex interaction<0.001). SPAfem was associated with LTL in women before and after correction (B=-0.195; 95% CI=-0.38 to -0.01; p=0.037) (p for sex interaction<0.001). LTL was also associated with age and sex-adjusted levels of hsCRP (p=0.012), sCD40L (p=0.042), homocysteine (p=0.006), creatinine (p=0.02), ApoA1 (p=0.01), Lp(a) (p=0.04) and HOMA-IR (p=0.008).

CONCLUSIONS

Our results support the telomere hypothesis and highlight potential differences in the biological mechanisms leading to intima-media thickening and/or plaque formation between vascular beds. They may provide insights into a novel treatment of antisenescence to prevent atherosclerosis.

Relationship between inflammatory markers, endothelial activation markers, and carotid intima-media thickness in HIV-infected patients receiving antiretroviral therapy

BACKGROUND

Human immunodeficiency virus (HIV)-infected patients are at increased risk of cardiovascular disease, which may be related to chronic inflammation and endothelial dysfunction despite virological control with antiretroviral therapy. The relationship between carotid intima-media thickness (IMT), a surrogate marker for cardiovascular disease, proinflammatory cytokines, and endothelial activation markers has not been fully explored in HIV-infected patients who are receiving antiretroviral therapy.

METHODS

We conducted a prospective, cross-sectional, observational study of treated HIV-infected patients and healthy control subjects to evaluate the relationship between carotid IMT, proinflammatory cytokines, endothelial activation biomarkers, and metabolic parameters in treated HIV-infected patients, compared with healthy control subjects.

RESULTS

We enrolled 73 HIV-infected patients and 21 control subjects. Common carotid artery and internal carotid artery IMT measurements, as well as tumor necrosis factor-alpha, high-sensitivity C-reactive protein, interleukin-6, myeloperoxidase, and soluble vascular cell adhesion molecule-1 levels were higher in the HIV-infected group. High-sensitivity C-reactive protein was the only biomarker that was positively correlated with carotid IMT in both groups. In the HIV-infected group, soluble vascular cell adhesion molecule-1 was positively correlated with all inflammatory cytokine levels. In multiple regression analysis, soluble vascular cell adhesion molecule-1, myeloperoxidase, and tumor necrosis factor-alpha levels were all associated with internal carotid artery IMT in the HIV-infected group, whereas age was associated with both common carotid artery and internal carotid artery IMT.

CONCLUSIONS

Enhanced endothelial activation, inflammation, and increased carotid IMT occur in HIV-infected patients despite antiretroviral therapy. Inflammatory markers are associated with endothelial activation, and both are associated with internal carotid artery IMT, supporting a potential role of inflammation in endothelial activation and cardiovascular disease in HIV infection.

Carotid and femoral arterial wall changes and the prevalence of clinical cardiovascular disease

Abstract

The Cyprus Study is a prospective cohort study of cardiovascular disease (CVD). Its aim is to determine the relationship of intima–media thickness (IMT) of the common carotid (IMTcc), maximum thickness of IMT in the carotid bifurcation (IMTmax), number of carotid and femoral bifurcations with plaque and total plaque thickness (TPT) (sum of the maximum plaque measurements taken from the four bifurcations scanned) with the prevalence of clinical CVD. A total of 767 individuals (46% male) over the age of 40 years were recruited from a mountain village and a town outside the capital Nicosia. In addition to clinical examination, carotid and common femoral bifurcations were scanned with ultrasound. After controlling for conventional risk factors, there was little evidence of an association of IMTcc with CVD prevalence. However, IMTmax and TPT were associated with 2.9-fold (1.22 to 7.07) and 6.87-fold (2.42 to 19.43) increased odds of CVD prevalence, respectively. In conclusion, the TPT and number of bifurcations with plaque are more strongly associated with the prevalence of CVD. These findings warrant investigation in prospective studies to document associations with incident CVD events.

Serum total homocysteine, folate, 5,10-methylenetetrahydrofolate reductase (MTHFR) 677C-->T genotype and subclinical atherosclerosis

OBJECTIVE

To determine the relationship of serum total homocysteine (tHcy), serum folate and 5,10-methylenetetrahydrofolate reductase (MTHFR) 677C-->T genotype with ultrasonic arterial wall measurements associated with subclinical atherosclerosis.

STUDY DESIGN

Cross-sectional analysis of 767 participants in an ongoing prospective study. Intima-media thickness (IMT) of the common carotid (IMTcc), IMT of the internal carotid including plaque when present (IMT(max)) and the sum of the thickest plaques present in both carotid and both common femoral bifurcations (total plaque thickness (TPT)) were measured using ultrasound.

RESULTS

People in the upper homocysteine quartile were more likely to have clinical cardiovascular disease (CVD) than those in the lowest three quartiles. They were also more likely to have plaques. The MTHFR 677C-->T genotype was not associated with any of the measures of subclinical atherosclerosis in either men or women but was the most important determinant of total homocysteine levels in men under 60 years of age.

CONCLUSIONS

Increased homocysteine levels but not MTHFR 677C-->T genotype, are associated with subclinical atherosclerosis and the presence of plaques. Our results indicate that measurements of blood levels of homocysteine and folate in people at intermediate risk for atherosclerotic CVD before symptoms occur, might improve risk stratification and facilitate the decision to provide folate/B vitamin intervention in primary prevention.

Structural alterations of the coronary arterial wall are associated with myocardial flow heterogeneity in type 2 diabetes mellitus

PURPOSE

To determine the relationship between carotid intima-media thickness (IMT), coronary artery calcification (CAC), and myocardial blood flow (MBF) at rest and during vasomotor stress in type 2 diabetes mellitus (DM).

METHODS

In 68 individuals, carotid IMT was measured using high-resolution vascular ultrasound, while the presence of CAC was determined with electron beam tomography (EBT). Global and regional MBF was determined in milliliters per gram per minute with (13)N-ammonia and positron emission tomography (PET) at rest, during cold pressor testing (CPT), and during adenosine (ADO) stimulation.

RESULTS

There was neither a relationship between carotid IMT and CAC (r = 0.10, p = 0.32) nor between carotid IMT and coronary circulatory function in response to CPT and during ADO (r = -0.18, p = 0.25 and r = 0.10, p = 0.54, respectively). In 33 individuals, EBT detected CAC with a mean Agatston-derived calcium score of 44 +/- 18. There was a significant difference in regional MBFs between territories with and without CAC at rest and during ADO-stimulated hyperemia (0.69 +/- 0.24 vs. 0.74 +/- 0.23 and 1.82 +/- 0.50 vs. 1.95 +/- 0.51 ml/g/min; p < or = 0.05, respectively) and also during CPT in DM but less pronounced (0.81 +/- 0.24 vs. 0.83 +/- 0.23 ml/g/min; p = ns). The increase in CAC was paralleled with a progressive regional decrease in resting as well as in CPT- and ADO-related MBFs (r = -0.36, p < or = 0.014; r = -0.46, p < or = 0.007; and r = -0.33, p < or = 0.041, respectively).

CONCLUSIONS

The absence of any correlation between carotid IMT and coronary circulatory function in type 2 DM suggests different features and stages of early atherosclerosis in the peripheral and coronary circulation. PET-measured MBF heterogeneity at rest and during vasomotor stress may reflect downstream fluid dynamic effects of coronary artery disease (CAD)-related early structural alterations of the arterial wall.

Increased carotid artery plaque score is an independent predictor of the presence and severity of coronary artery disease

OBJECTIVES

Carotid ultrasonography is noninvasive and effective for the assessment of atherosclerotic lesions. The relationship between carotid ultrasound findings and presence and severity of coronary artery disease (CAD) was examined in Japanese patients.

METHODS AND RESULTS

Subjects were 116 patients who underwent carotid ultrasonography and coronary angiography. In carotid ultrasonography, mean-intima-media thickness (IMT), common carotid artery max IMT, bifurcation max IMT, plaque number, and plaque score (PS). The coronary angiographic data was obtained in the same period as carotid ultrasonography was performed. Patients were divided into two groups based on the presence or absence of coronary artery stenosis (CAS and non-CAS) and CAS group was further categorized into three groups, 1 vessel disease (1VD), 2VD, and 3VD. Physical findings, biochemical data, and carotid ultrasonogram data between the groups were compared. Items showing a significant difference between CAS and non-CAS were age, gender (male), incidence of diabetes and dyslipidemia, fasting blood sugar (FBS), triglyceride, HDL-cholesterol (HDL-C), high-sensitivity C-reactive protein, and all carotid ultrasound findings. All of the above parameters also showed a significant difference between four different severity groups. Stepwise logistic regression analysis was performed to determine which factors predict the presence and/or severity of CAS. High PS showed the strongest predictive value for both and followed by low HDL-C and high FBS. The cut-off value of PS obtained by receiver operating characteristic curve for predicting the presence of CAS was 1.9.

CONCLUSIONS

Assessment of PS by carotid ultrasonography together with other risk factor assessment was clinically relevant to predict the presence and severity of CAS.

Usefulness of high-frequency vascular ultrasound imaging and serum inflammatory markers to predict plaque rupture in patients with stable and unstable angina pectoris

It remains unclear what kind of morphologic and biochemical features best predict plaque rupture in patients with angina pectoris (AP). This study aimed to investigate whether combined high-frequency vascular ultrasound imaging and measurements of serum inflammatory biomarkers can predict coronary plaque ruptures in patients with AP. The study population consisted of 20 patients with stable AP and 40 patients with unstable AP. High-frequency vascular ultrasound imaging was performed in the 2 groups to measure intima-media thickness, the plaque acoustic density of the common carotid arteries, and the flow-mediated dilation of the brachial arteries. Serum lipid profile and inflammatory biomarkers were measured in all patients. Using intravascular ultrasound, a list of coronary imaging parameters was obtained. A multivariate logistic regression model was applied to calculate the odds ratio of each parameter to predict coronary plaque ruptures detected by intravascular ultrasound. Of 139 coronary artery plaques identified by intravascular ultrasound, 48 plaques (9 in stable AP and 39 in unstable AP) developed ruptures. Among measured parameters, the values of carotid intima-media thickness, coronary external elastic membrane area, plaque area, plaque burden, plaque eccentric index and remodeling index, serum high-sensitivity C-reactive protein, soluble intercellular adhesion molecule-1, and soluble vascular cell adhesion molecule-1 were significantly higher in unstable AP than in stable AP (p <0.05 to 0.01). Of these parameters, carotid intima-media thickness, serum high-sensitivity C-reactive protein, and the coronary remodeling index were found to be significant predictors of coronary plaque rupture, with odds ratios of 9.51 (95% confidence interval 1.29 to 21.81), 3.02 (95% confidence interval 1.01 to 7.65), and 0.01 (95% confidence interval 0.00 to 0.34), respectively. In conclusion, combined high-frequency ultrasound imaging of coronary and carotid arteries and measurements of serum inflammatory markers are able to predict coronary plaque ruptures in patients with AP.

Effect of high-dose alpha-tocopherol supplementation on biomarkers of oxidative stress and inflammation and carotid atherosclerosis in patients with coronary artery disease

BACKGROUND

Oxidative stress and inflammation are crucial in atherogenesis. alpha-Tocopherol is both an antioxidant and an antiinflammatory agent.

OBJECTIVE

We evaluated the effect of RRR-alpha-tocopherol supplementation on carotid atherosclerosis in patients with stable coronary artery disease (CAD) on drug therapy.

DESIGN

Randomized, controlled, double-blind trial compared RRR-alpha-tocopherol (1200 IU/d for 2 y) with placebo in 90 patients with CAD. Intimal medial thickness (IMT) of both carotid arteries was measured by high-resolution B-mode ultrasonography at 0, 1, 1.5, and 2 y. At 6-mo intervals, plasma alpha-tocopherol concentrations, C-reactive protein (CRP), LDL oxidation, monocyte function (superoxide anion release, cytokine release, and adhesion to endothelium), and urinary F(2)-isoprostanes were measured.

RESULTS

alpha-Tocopherol concentrations were significantly higher in the alpha-tocopherol group but not in the placebo group. High-sensitivity CRP concentrations were significantly lowered with alpha-tocopherol supplementation than with placebo (32%; P < 0.001). alpha-Tocopherol supplementation significantly reduced urinary F(2)-isoprostanes (P < 0.001) and monocyte superoxide anion and tumor necrosis factor release compared with baseline and placebo (P < 0.001). No significant difference was observed in the mean change in total carotid IMT in the placebo and alpha-tocopherol groups. In addition, no significant difference in cardiovascular events was observed (P = 0.21).

CONCLUSIONS

High-dose RRR-alpha-tocopherol supplementation in patients with CAD was safe and significantly reduced plasma biomarkers of oxidative stress and inflammation but had no significant effect on carotid IMT during 2 y.

Increased carotid intima media thickness and cardiac biomarkers in HIV infected children

OBJECTIVES

To assess carotid intima media thickness (IMT) and cardiac biomarkers in HIV infected children on antiretroviral therapy (ART).

METHODS

This was a single site, cross sectional, controlled observational study. We assessed carotid IMT, homocysteine, high-sensitivity C-reactive protein and myeloperoxidase levels in HIV infected children on stable ART for >or= 6 months. Carotid IMT was reported as internal carotid artery (ICA) and common carotid artery (CCA) thickness; left and right sides were measured separately. Groups were compared using appropriate two-sample tests.

RESULTS

Of the 62 subjects enrolled, 31 were HIV positive (50%), 66% were female, and 69% were African-American. Median CD4% was 32% and 26 patients (84%) had HIV-1 RNA< 400 copies/ml. Sixteen patients had been taking protease inhibitors for a median duration of 27 months. None had hypertension or smoked. HIV infected children had higher HOMA-IR, waist-to-hip ratio, cholesterol, triglycerides, myeloperoxidase and lower homocysteine levels. Left and right CCA IMT, and left and right ICA IMT were significantly higher in the HIV infected group. Significant predictors of carotid IMT measurements in uninfected controls were body mass index and homocysteine, but only the duration of ARV therapy was predictive of IMT in the HIV infected group.

CONCLUSION

Higher levels of carotid IMT and some cardiac markers were found in ART treated HIV infected children when compared to matched uninfected controls. These results suggest that HIV infected children receiving ART may be at increased risk of cardiovascular disease.

Arterial Ultrasonography and Tonometry as Adjuncts to Cardiovascular Risk Stratification

Myocardial infarction and stroke often occur without prior warning in asymptomatic individuals. Identifying individuals at risk is important for cost-effective use of preventive therapies. Algorithms based on risk factors statistically associated with cardiovascular events classify individuals into high-risk, intermediate-risk, or low-risk categories. However, more than one-third of adults in the U.S. are in the intermediate-risk category, and decisions regarding therapy are challenging in this subset. Testing for alterations in arterial function and structure that predate cardiovascular events may help refine cardiovascular risk assessment in the intermediate-risk group and identify candidates for aggressive therapy. Vascular ultrasonography and tonometry are promising test modalities for assessment of arterial function and structure in asymptomatic subjects. Several prospective studies have shown that measures of arterial function and structure provide prognostic information incremental to conventional risk factors. Standardization of methodology and establishment of quality control standards in the performance of these tests could facilitate their integration into clinical practice as adjuncts to existing cardiovascular risk stratification algorithms.